Sir John made two incursions upon the Mohawk valley during the remainder of the war. His first blow was as sudden as it was unexpected. On Sunday, the 21st of May, 1780, he entered the north part of Johnstown at the head of five hundred men, composed of some British troops, a detachment of his own regiment of Royal Greens, and about two hundred Indians and Tories. Sir John had penetrated the country by way of Lake Champlain to Crown Point, and thence through the woods by way of Crane mountain (in the present town of Thurman, in Warren county), to the Sacandaga river; and so entirely unawares had he stolen upon the sleeping inhabitants, that he arrived in the heart of the country undiscovered, except by the resident loyalists, who were probably in the secret. Before he reached the old baronial hall at Johnstown-the home of his youth, and for the recovery of which he made every exertion that courage and enterprise could put forth - Sir John divided his forces into two detachments, leading one in person, in the first instance, directly to the Hall, and thence through the village of Johnstown, while the other was sent through a more eastern settlement to strike the Mohawk river at or below Tribe's Hill, whence it was directed to sweep up the river through the ancient Dutch village of Caughnawaga to the Cayadutta creek at which place a junction was to be formed with Sir John himself. This disposition of his forces was made at the still hour of midnight a time when the inhabitants were not only buried in slumber, but wholly unsuspicious of approaching danger. What officer was in command of the eastern division is not known, but it was one of the most stealthy and murderous expeditions, murderous in its character, though but few were killed, and the most disgraceful, too, that marked the progress of the war in that region. During the night-march of this division, and before reaching the river, they attacked the house of Mr. Lodowick Putnam, who, together with his son, was killed and scalped. The house of a Mr. Stevens was then assailed and burnt, and its owner killed. Arriving at Tribe's Hill, they murdered three men by the names of Hansen, Platts, and Aldridge. Hansen, who was a captain of militia, was killed by an Indian to whom he had formerly shown great kindness, and who had in return expressed much gratitude. The houses of all, it is believed, were plundered before the application of the torch. Proceeding toward Caughnawaga, about dawn, they arrived at the house of Colonel Visscher - occupied at the time by himself, his mother, and his two brothers. It was immediately assailed. Alarmed at the sounds without, the colonel instantly surmised the cause, and being armed, determined, with his brothers, to defend the house to the last. They fought bravely for a time, but the odds were so fearfully against them that the house was soon carried by storm. The three brothers were instantly stricken down and scalped, and the torch applied to the house. Having thus completed their work, the enemy proceeded on their way up the river. Fortunately, however, the colonel himself was only wounded. But grievously wounded as he was, he succeeded in removing the mangled bodies of his two brothers from the house before the burning timbers fell in. His own wounds were dressed, and he lived many years afterward. Mrs. Visscher, his aged mother, was also severely wounded by being knocked on the head by the hatchet of an Indian, but she also survived. The slaughter along the Mohawk, to the village of Caughnawaga, would have been greater, but for the alertness of Major Van Vrank, who, eluding the enemy, ran ahead and gave the alarm, thus enabling many of the inhabitants to fly across the river.
Meantime Sir John proceeded with his division through the village of Johnstown, stopping before it was yet light at what was once his own hall, where he made two prisoners. Directing his course for the confluence of the Cayadutta with the Mohawk, Sir John arrived at the residence of Sampson Sammons, a staunch Whig. The eldest of Mr. Sammons's sons was then the lessee of the Johnson farm at the Hall, which had been sold by the committee of sequestrations, and which he was then cultivating; and Thomas, the youngest, had risen at an unwonted hour in order to feed his horses, and go over to the Hall to work with his brother. As he passed out of the house a hand was laid upon his shoulder, with the words- - "You are my prisoner!" In such perfect stillness had the enemy approached, that not a sound of a footstep was heard, until the younger Sammons was thus arrested, and the house immediately surrounded. One of the officers, with several soldiers, instantly entered the house, and ordered the family to get up, and surrender themselves as prisoners. Two other sons, Jacob and Frederick, who were in bed in the second story, sprang upon their feet immediately, and seized their arms. The officer, who was a Tory, and acquainted with the family, called to them by name, and promised quarter on condition of their surrender. Jacob inquired whether there were Indians with them, adding, that if there were, he and his brother would not be taken alive. On being assured to the contrary, the brothers descended the stairs and surrendered. The females were not taken as prisoners, but the father and sons were directed to make ready to march forthwith, and the house having been thoroughly ransacked for plunder, Sir John, with his troops and prisoners, proceeded to the river at Caughnawaga. The whole army now set their faces westward, traversing the Mohawk valley several miles, burning every building not owned by a loyalist, killing sheep and black cattle, and taking all the horses that could be found for their own use. Returning again to Caughnawaga, the torch was applied to every building, excepting the church; a number of prisoners were made, and several persons killed. Nine aged men were slain in the course of this march, of whom four were upwards of eighty. From Caughnawaga Sir John retraced his steps to Johnstown, passing the premises of Mr. Sammons, where the work of destruction was completed by firing all the buildings, leaving the females of the family houseless, and taking away the seven horses which were in the stables.